Walter R. Booth's THE AIRSHIP DESTROYER (1909)
Early SciFi film with war Zeppelin like aircrafts destroying civilian areas.
Emazingly enough, this film anounces not so much the WWI, which hadn't occured yet, but WWII (the Blitz, numerous destroyed cities and Millions of civilians killed...) Films have too often dreadful premonitions...
Quite realistic, even if it has this nice Jules Verne and Georges Melies look.
more info on http://www.imdb.com/title/tt0000790/